JP2008158173A - Screen and rear projector - Google Patents

Abstract

[PROBLEMS] To provide a screen capable of easily changing the directivity of the screen and improving the luminance of image light viewed from an observer in either the left or right direction.
A screen 6 includes a Fresnel lens 61, a lenticular lens 62, a black stripe 63, and a viewing angle adjusting member 64. The lenticular lens 62 emits the parallel light converted by the Fresnel lens 61 from between the black stripes 63. The viewing angle adjusting member 64 includes a plurality of viewing angle adjusting elements 641, and the partial light LS divided by the cylindrical lens 621 and the black stripe 63 is incident on each viewing angle adjusting element 641 from the back surface 642. And the optical path of each partial light LS can be changed by moving the viewing angle adjusting member 64 in either the left or right direction.
[Selection] Figure 3

Description

  The present invention relates to a screen and a rear projector including the screen.

  2. Description of the Related Art Conventionally, there is known a rear projector that displays an enlarged image of image light on a transmissive screen. Such a transmissive screen generally has a layered structure in which a Fresnel lens and a lenticular lens are stacked. The image light passes through the Fresnel lens, becomes light substantially parallel to the normal direction of the screen, and enters the lenticular lens. The light incident on the lenticular lens is diverged in the horizontal direction of the screen and passes through the screen. Thereby, the viewing angle of the screen can be widened, and the observer can observe the image light from various directions.

Here, since the viewing angle of the screen is determined and fixed by the shape of the lenticular lens, etc., when the observer observes the screen from a position deviating from the viewing angle, for example, from the left or right direction of the screen, The brightness of the image light viewed from the observer is reduced. In addition, when the viewing angle of the screen is widened, the amount of light directed toward the observer decreases, so that there is a problem that the luminance of image light viewed from the observer decreases.
On the other hand, a screen capable of changing the directivity is known (for example, see Patent Document 1). The directivity characteristic refers to a light amount characteristic with respect to a deviation angle from the normal line direction of the screen.
In the transmissive screen described in Patent Document 1, a dispersive liquid crystal panel that can change the directivity of the screen by applying a voltage is disposed between the Fresnel lens and the lenticular lens. Then, by changing the directivity so as to narrow the viewing angle, the amount of light directed to the observer in the front direction of the screen is increased, and the luminance of the image light viewed from the observer is improved.

Japanese Patent Laid-Open No. 5-97023

  However, the transmissive screen described in Patent Document 1 can improve the brightness of image light viewed from the frontal observer, but is located at a position outside the viewing angle, for example, the observer in either the left or right direction There is a problem that the brightness of the image light viewed from the viewpoint cannot be improved.

  An object of the present invention is to provide a screen capable of easily changing the directivity of the screen and improving the luminance of image light viewed from an observer in either the left or right direction, and a rear projector including the screen. There is to do.

  The present invention is a transmissive screen that projects image light projected from the back side to the front side, a dividing member that divides and emits the image light into a plurality of partial lights, and a plurality of the partial lights A viewing angle adjusting member that reflects and changes the optical path internally, and one of the viewing angle adjusting member and the dividing member is moved relative to the other to adjust the viewing angle. The member is characterized by changing an optical path of the plurality of partial lights.

  According to such a configuration, one of the viewing angle adjusting member and the dividing member is moved relative to the other, so that the viewing angle adjusting member changes the optical paths of the plurality of partial lights. Can do. Therefore, the directivity of the screen can be easily changed. In addition, for example, a viewing angle adjustment member is formed so that the optical paths of a plurality of partial lights are reflected inside and changed in either the left or right direction of the screen, so that it can be viewed from an observer in either right or left direction. The brightness of the image light can be improved.

  In the present invention, the screen is formed in a substantially rectangular shape, the dividing member divides the image light into a direction of one side of the screen with a substantially uniform width, and the viewing angle adjusting member includes the plurality of viewing angle adjusting members. A plurality of viewing angle adjusting elements on which the partial lights are incident; the viewing angle adjusting element is formed of a columnar body; and the viewing angle adjusting member is moved in the direction of the one side, thereby It is preferable to change the optical path by reflecting the side surface of the viewing angle adjusting element.

  Here, in the lenticular lens described above in the transmission type screen, generally, a plurality of cylindrical lenses having a light incident surface formed on a flat surface and a light exit surface formed on a convex lens surface are arranged in the horizontal direction of the screen. It is arranged in a sheet form. An antireflection film is formed in the recesses between the cylindrical lenses so that external light is not reflected on the light exit surfaces of the cylindrical lenses. That is, the image light projected from the back side of the screen is divided in the horizontal direction by each cylindrical lens and each antireflection film and emitted as a plurality of partial lights. It is substantially parallel to the normal direction.

  Therefore, for example, the splitting member of the present invention is composed of a lenticular lens and a reflection separation film, and has a viewing angle adjustment provided with a plurality of viewing angle adjusting elements on the light exit surface side of the lenticular lens. The screen of the present invention can be configured by arranging members. Thereby, the configuration of the screen can be simplified. In each viewing angle adjusting element, the viewing angle adjusting member is moved in the horizontal direction of the screen, so that the optical path of the partial light can be reflected and changed by the side surface of the viewing angle adjusting element.

  In the present invention, the viewing angle adjusting element includes a back surface facing the dividing member and receiving the partial light, and two side surfaces facing in the direction of the one side, and the two side surfaces have the viewing angle. When the adjustment member is moved in the direction of the one side, the light substantially parallel to the principal ray of the partial light is reflected on one of the two side surfaces and is different from the back surface. It is preferable to be formed so as to be injected from

  According to such a configuration, when the viewing angle adjustment member is moved in the direction of one side of the screen, the light substantially parallel to the principal ray of the partial light incident from the back surface is one of the two side surfaces. Since the light is reflected from the side surface and emitted from a surface different from the back surface, for example, the other side surface, the viewing angle adjusting member can be moved in the direction of one side of the screen to change the optical path of the partial light. . Moreover, since the light substantially parallel to the principal ray of the partial light incident from the back surface is emitted from a surface different from the back surface, it can be emitted from each viewing angle adjusting element without losing the light amount.

In the present invention, the viewing angle adjusting element is preferably a substantially equilateral triangular prism when the back surface and the two side surfaces are respectively extended to form a columnar body.
According to such a configuration, light that is substantially parallel to the partial light incident from the back surface travels in a direction substantially orthogonal to the other side surface when reflected on one side surface, and is not substantially refracted from the other side surface. Since it is emitted, it can be emitted from each viewing angle adjusting element without losing the amount of light.

In the present invention, it is preferable that chief rays of the plurality of partial lights are substantially parallel to each other.
According to such a configuration, since the optical paths of the partial lights can be easily aligned in a predetermined direction, the amount of light directed toward the observer can be increased, and the luminance of the image light viewed from the observer is improved. be able to.

A rear projector according to the present invention includes an image projection device that modulates light emitted from a light source according to image information to form image light, and projects the image light in an enlarged manner, and the screen described above. To do.
According to such a configuration, since the rear projector includes the screen described above, it is possible to receive the same operations and effects as those of the screen described above. In addition, for example, by operating a remote controller or the like so that one of the viewing angle adjustment member and the split member can be moved, the observer of the projector can change the optical path of each partial light in its own direction. can do.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Main configuration of rear projector 1]
FIG. 1 is a vertical sectional view of the rear projector 1.
As shown in FIG. 1, the rear projector 1 is roughly configured by a cabinet 2, a projector unit 3 as an image projection device, a control unit 4, a reflection mirror 5, and a screen 6.

As shown in FIG. 1, the cabinet 2 is configured in a box shape whose back side (right side in FIG. 1) is inclined, and houses and arranges the projector unit 3, the control unit 4, and the reflection mirror 5 therein. Although not specifically shown, the cabinet 2 includes a power supply unit that supplies power to each component of the rear projector 1, in addition to the projector unit 3, the control unit 4, and the reflection mirror 5, and a rear unit. A cooling unit for cooling the inside of the projector 1, a sound output unit for outputting sound, and the like are arranged.
An opening 21 having a rectangular shape in plan view is formed on the front side of the cabinet 2 (left side in FIG. 1), and the screen 6 is supported and fixed to the periphery of the opening 21.

The projector unit 3 is disposed on the bottom surface in the cabinet 2, forms the image light L based on the image signal output from the control unit 4, and magnifies and projects the image light L toward the reflection mirror 5. The specific configuration of the projector unit 3 will be described later.
Although not specifically illustrated, the control unit 4 includes, for example, a tuner, an IF (Intermediate Frequency) circuit, an audio detection circuit, a video detection circuit, an amplification circuit, and a CPU (Central Processing Unit). The projector unit 3 is comprehensively controlled. In addition, the control unit 4 performs an operation according to an operation of a remote controller (not shown) or an operation panel (not shown) by an observer of the rear projector 1, for example, power on / off, channel switching, and the like.

The reflection mirror 5 is disposed on the upper back side in the cabinet 2 and reflects the image light L projected by the projector unit 3 to the back side of the screen 6.
The screen 6 has a rectangular shape and is supported and fixed to the periphery of the opening 21 of the cabinet 2. The screen 6 is a transmissive screen that displays the projected image by projecting the image light L projected from the back side to the front side. The specific configuration of the screen 6 will be described later.

[Configuration of Projector Unit 3]
FIG. 2 is a schematic diagram illustrating a schematic configuration of an optical system configured in the projector unit 3.
As shown in FIG. 2, the projector unit 3 includes an integrator illumination optical system 31, a color separation optical system 32, a relay optical system 33, an optical device 34, and a projection lens 35.

  The integrator illumination optical system 31 is an optical system for making light emitted from the light source uniform in illuminance within the plane orthogonal to the illumination optical axis. As shown in FIG. 2, the integrator illumination optical system 31 includes a light source device 311 including a discharge light source lamp 3111 and a reflector 3112 such as an ultrahigh pressure mercury lamp, a metal halide lamp, and a xenon lamp, a first lens array 312, and the like. , A second lens array 313, a polarization conversion element 314, and a superimposing lens 315. The light emitted from the light source lamp 3111 is aligned in the emission direction by the reflector 3112, divided into a plurality of partial lights by the first lens array 312, and forms an image in the vicinity of the second lens array 313. Each partial light emitted from the second lens array 313 is incident so that the central axis thereof is perpendicular to the incident surface of the polarization conversion element 314 at the subsequent stage, and is converted into substantially one type of linearly polarized light by the polarization conversion element 314. It is injected. A plurality of partial lights emitted from the polarization conversion element 314 as linearly polarized light and passed through the superimposing lens 315 are superimposed on three liquid crystal panels (to be described later) of the optical device 34.

The color separation optical system 32 includes two dichroic mirrors 321 and 322 and a reflection mirror 323, and the dichroic mirrors 321 and 322 and the reflection mirror 323 emit a plurality of partial lights emitted from the integrator illumination optical system 31. It has the function of separating into three color lights of red, green and blue.
The relay optical system 33 includes an incident side lens 331, a relay lens 332, and reflection mirrors 333 and 334, and has a function of guiding the color light separated by the color separation optical system 32 to a liquid crystal panel described later.

  The optical device 34 modulates the three color lights emitted from the color separation optical system 32 according to image information, and combines the modulated color lights to form a color image. As shown in FIG. 2, the optical device 34 includes three liquid crystal panels 341 (R-color light liquid crystal panel 341R, G-color light liquid crystal panel 341G, and B-color light liquid crystal panel 341B as light modulation devices. ) And an incident-side polarizing plate 342 and an emitting-side polarizing plate 343 disposed on the light incident side and the light emitting side of the liquid crystal panel 341, respectively, and a cross dichroic prism 344.

The incident-side polarizing plate 342 receives light of each color whose polarization direction is aligned in approximately one direction by the polarization conversion element 314. Of the incident light, the polarization axis of the light aligned by the polarization conversion element 314 is substantially the same. Only polarized light in the direction is transmitted, and other light is absorbed. The incident-side polarizing plate 342 has a configuration in which a polarizing film is pasted on a translucent substrate such as sapphire glass or quartz.
Although not specifically illustrated, the liquid crystal panel 341 has a configuration in which a liquid crystal as an electro-optical material is hermetically sealed between a pair of transparent glass substrates, and according to a drive signal output from the control device, The alignment state of the liquid crystal is controlled, and the polarization direction of the polarized light emitted from the incident side polarizing plate 342 is modulated.

The exit-side polarizing plate 343 has substantially the same configuration as the incident-side polarizing plate 342, and only light having a polarization axis orthogonal to the light transmission axis in the incident-side polarizing plate 342 out of the light emitted from the liquid crystal panel 341. It transmits light and absorbs other light.
The cross dichroic prism 344 is an optical element that synthesizes modulated light (optical image) modulated for each color light emitted from the emission-side polarizing plate 343 to form image light (color image). The cross dichroic prism 344 has a square shape in plan view in which four right-angle prisms are bonded together, and two dielectric multilayer films are formed on the interface where the right-angle prisms are bonded together. These dielectric multilayer films are emitted from the liquid crystal panel 341 (341G) disposed on the side facing the projection lens 35 and transmit the color light via the emission side polarizing plate 343, and the remaining two liquid crystal panels 341 (341R). , 341G), and reflects each color light via each exit-side polarizing plate 343. In this way, the color lights modulated by the liquid crystal panels 341 are combined to form a color image.

The projection lens 35 is configured as a combined lens in which a plurality of lenses are combined. The projection lens 35 forms image light L based on the color image formed by the cross dichroic prism 344 and enlarges and projects the image light L toward the reflection mirror 5.
In the projector unit 3 described above, the image light L (linearly polarized light) is polarized in order to suppress light loss due to light absorption by the reflection mirror 5 when it is enlarged and projected from the projection lens 35 and reflected by the reflection mirror 5. The direction is set to be linearly polarized light (S-polarized light) perpendicular to the incident surface with respect to the reflection mirror 5 (see FIG. 1).

[Configuration of Screen 6]
FIG. 3 is a horizontal sectional view showing a schematic configuration of the screen 6.
As shown in FIG. 3, the screen 6 includes a Fresnel lens 61, a lenticular lens 62, a black stripe 63, and a viewing angle adjustment member 64.
As shown in FIG. 3, the Fresnel lens 61 is arranged on the back side (the incident side of the image light L), and converts the image light L incident through the reflection mirror 5 into parallel light.

As shown in FIG. 3, the lenticular lens 62 has a sheet-like shape in which a plurality of cylindrical lenses 621 having a light incident surface formed as a flat surface and a light exit surface formed as a convex lens surface are arranged in the horizontal direction of the screen 6. And is disposed downstream of the optical path of the Fresnel lens 61.
As shown in FIG. 3, the black stripe 63 is an antireflection film formed in a recess between the cylindrical lenses 621. The black stripe 63 prevents external light incident from the front side toward the screen 6 from being reflected.

The lenticular lens 62 emits the parallel light converted by the Fresnel lens 61 from between the black stripes 63. That is, the image light L emitted from the lenticular lens 62 is divided by the cylindrical lenses 621 and the black stripes 63 with a substantially uniform width in the horizontal direction of the screen 6 and emitted as a plurality of partial lights LS. Each partial light LS is emitted from the lenticular lens 62 with a predetermined spread in the horizontal direction of the screen 6, but the central axis (hereinafter referred to as a principal ray) of each partial light LS is It is substantially parallel to the normal direction.
In the present embodiment, the dividing member of the present invention includes a lenticular lens 62 and a black stripe 63.

As shown in FIG. 3, the viewing angle adjusting member 64 is configured in a sheet shape by arranging a plurality of viewing angle adjusting elements 641 (columnar bodies) made of quartz glass formed in a regular triangular prism shape in the horizontal direction of the screen 6. The lenticular lens 62 is disposed in the latter stage of the optical path, that is, on the light exit surface side.
Each viewing angle adjustment element 641 includes a back surface 642, a right side surface 643, and a left side surface 644. Further, each side of the equilateral triangle in each viewing angle adjusting element 641 is formed to have the same length as the pitch (1 pitch) between the principal rays of each partial light LS, and the principal rays of each partial light LS and the back surface 642 The center axis can be aligned. Therefore, each partial light LS divided by each cylindrical lens 621 and the black stripe 63 enters each viewing angle adjustment element 641 from the back surface 642.

  The viewing angle adjusting member 64 is moved in the right (arrow RD in FIG. 3) direction or the left (arrow LD in FIG. 3) direction as viewed from the front side of the screen 6 by a stepping motor (not shown). It is configured to be movable in the horizontal direction. The stepping motor moves the viewing angle adjusting member 64 in a range of 0.5 pitch stepwise in either the left or right direction according to the operation of the remote controller or the operation panel under the control of the control unit 4 described above. Move within. That is, the observer of the rear projector 1 can arbitrarily move the viewing angle adjusting member 64 in either the left or right direction of the screen 6.

[Method of changing directivity of screen 6]
Next, an optical path of light substantially parallel to the principal ray of each partial light LS incident from the back surface 642 of each viewing angle adjustment element 641 will be described with reference to FIGS. 4 and 5 as well.
FIG. 4 is a diagram illustrating an optical path of light substantially parallel to the principal ray of each partial light LS when the viewing angle adjusting member 64 is moved in the right direction. FIG. 5 is a diagram showing an optical path of light substantially parallel to the principal ray of each partial light LS when the viewing angle adjusting member 64 is moved in the left direction.
Here, in FIGS. 3 to 5, among the lights substantially parallel to the principal rays of the partial lights LS, the rightmost light as viewed from the front side of the screen 6 is the light A, and the leftmost light is the light. This will be described as B.

  First, as shown in FIG. 3, when the lenticular lens 62 and the viewing angle adjusting member 64 are in the initial positions, that is, when the principal rays of the respective partial lights LS and the central axis of the back surface 642 are aligned. The light A and B incident from the back surface 642 travels straight inside the viewing angle adjusting element 641. The light A is incident on the right side surface 643 at an incident angle of about 30 °, and the light B is incident on the left side surface 644 at an incident angle of about 30 °. Here, if the refractive index of the quartz glass forming the viewing angle adjusting element 641 is n1 = 1.5 and the refractive index of air is n2 = 1.0, the light A is emitted from the viewing angle adjusting element 641 into the air. The critical angle θ in the case of incidence is calculated by the following formula (1) according to Snell's law.

  θ = arcsin (n2 / n1) (1)

  Therefore, since the critical angle θ is approximately 42 ° and the incident angle is approximately 30 °, the lights A and B are totally reflected on the right side surface 643 and the left side surface 644, that is, one side surface, respectively. The lights A and B are incident on the left side surface 644 and the right side surface 643 at an angle of about 90 °, respectively, and are not substantially refracted from the left side surface 644 and the right side surface 643, that is, from a surface different from the back surface 642. It is injected.

  Next, as shown in FIG. 4, when the viewing angle adjustment member 64 is moved to the right, the light A and B incident from the back surface 642 travels straight inside the viewing angle adjustment element 641. The lights A and B are incident on the left side surface 644 at an incident angle of approximately 30 °. Therefore, since the critical angle θ is approximately 42 °, the lights A and B are totally reflected by the left side surface 644. The lights A and B are incident on the right side surface 643 at an angle of about 90 °, and are emitted from the right side surface 643 without being refracted.

  Next, as shown in FIG. 5, when the viewing angle adjusting member 64 is moved to the left, the light A and B incident from the back surface 642 travels straight inside the viewing angle adjusting element 641. The lights A and B are incident on the right side surface 643 at an incident angle of approximately 30 °. Therefore, since the critical angle θ is approximately 42 °, the lights A and B are totally reflected by the right side surface 643. Lights A and B are incident on the left side surface 644 at an angle of about 90 °, and are emitted from the left side surface 644 without being substantially refracted.

  Therefore, when the lenticular lens 62 and the viewing angle adjusting member 64 are in the initial positions, the light substantially parallel to the principal ray of each partial light LS is divided into the right side 643 direction and the left side 644 direction, and the viewing angle. The light is emitted from the adjustment element 641. When the viewing angle adjustment member 64 is moved in the right direction, the light substantially parallel to the principal ray of each partial light LS is emitted in the direction of the right side surface 643, and the viewing angle adjustment member 64 is moved in the left direction. In this case, light substantially parallel to the principal ray of each partial light LS is emitted in the direction of the left side surface 644. Further, as described above, since each partial light LS is emitted from the lenticular lens 62 with a predetermined spread in the horizontal direction of the screen 6, the partial light LS emitted from each viewing angle adjustment element 641 is It is emitted with a spread around the chief ray.

  As described above, the screen 6 can display the projected image by projecting the image light L projected from the back side to the front side, and by moving the viewing angle adjusting member 64 in either the left or right direction. The optical path of each partial light LS can be changed.

The rear projector 1 according to the present embodiment has the following effects.
(1) Since the optical path of each partial light LS can be changed by moving the viewing angle adjusting member 64 stepwise in either the left or right direction, the directivity characteristics of the screen 6 can be easily changed. it can.
(2) When the viewing angle adjusting member 64 is moved in the right direction, light substantially parallel to the principal ray of each partial light LS is emitted in the direction of the right side surface 643, and the viewing angle adjusting member 64 is moved in the left direction. When moved, the light substantially parallel to the principal ray of each partial light LS is emitted in the direction of the left side surface 644, so that the brightness of the image light viewed from the observer in either the left or right direction is improved. Can do.

(3) Since the viewing angle adjusting member 64 is disposed on the light exit surface side of the lenticular lens 62, the configuration of the screen 6 can be simplified.
(4) Since the light substantially parallel to the principal ray of the partial light LS is emitted without being refracted from a surface different from the back surface 642, the light can be emitted from each viewing angle adjusting element 641 without losing the amount of light. it can.
(5) Since the principal rays of the partial lights are substantially parallel to the normal direction of the screen 6, the optical paths of the partial lights LS can be easily aligned in a predetermined direction. Therefore, the amount of light directed toward the observer can be increased, and the luminance of the image light L viewed from the observer can be improved.
(6) The observer of the rear projector 1 can change the optical path of each partial light in his / her direction by arbitrarily moving the viewing angle adjusting member 64 in the left or right direction of the screen 6.

[Modification of Embodiment]
It should be noted that the present invention is not limited to the above-described embodiment, and modifications, improvements, etc. within a scope that can achieve the object of the present invention are included in the present invention.
In the above embodiment, the viewing angle adjustment member 64 is configured to be movable in either the left or right direction by the stepping motor. However, the screen is set so that the observer can move the viewing angle adjustment member by manual operation. May be configured. In this case, the directivity of the screen can be changed without continuing to apply a voltage as in the screen described in Patent Document 1 described above.
In the embodiment, the optical path of each partial light LS is changed by moving the viewing angle adjusting member 64 in either the left or right direction. For example, the lenticular lens 62 is moved in either the left or right direction. In short, any one of the dividing member and the viewing angle adjusting member may be configured to be movable.

In the embodiment, the plurality of cylindrical lenses 621 are arranged in the horizontal direction of the screen 6, but a plurality of cylindrical lenses 621 may be arranged in the vertical direction of the screen 6, for example. In this case, a plurality of viewing angle adjusting elements 641 may be arranged in the vertical direction of the screen 6.
In the above embodiment, the dividing member is composed of the lenticular lens 62 and the black stripe 63. For example, the Fresnel lens 61 is arranged so as to divide the image light L in the horizontal direction of the screen 6 with a substantially uniform width. Black stripes may be formed on the substrate. Furthermore, black stripes may be formed in a lattice pattern on spherical lenses arranged in a matrix, and partial light divided vertically and horizontally may be emitted. In short, it is only necessary that the image light can be divided into a plurality of partial lights.

In the above embodiment, the principal ray of the partial light LS divided by each cylindrical lens 621 and the black stripe 63 is substantially parallel to the normal line direction of the screen 6, but may not be substantially parallel. As long as each partial light can be incident on each viewing angle adjusting element.
In the above-described embodiment, each viewing angle adjustment element 641 is made of quartz glass, but may be made of other materials such as quartz, and in short, may be made of a material having optical transparency.

In the embodiment, each viewing angle adjustment element 641 is formed in a regular triangular prism shape, but may be formed in a shape other than this, and in short, the optical path of each partial light is changed to the side surface of the viewing angle adjustment element. It is sufficient if it can be reflected and changed.
For example, the shape of the viewing angle adjusting element may be a quadrangular prism having a trapezoidal cross section with the front side of the screen 6 being a plane in the viewing angle adjusting element 641, and further, the front side of the screen 6 is a curved surface. It may be a shape. In this case, when the lenticular lens 62 and the viewing angle adjusting member are at the initial position, a part of the partial light LS is emitted to the front side of the screen 6, so that the observer from the front direction The brightness of the viewed image light can be improved.

In addition, for example, as described above, when the dividing member is formed so as to emit partial light that is divided vertically and horizontally, a viewing angle adjustment is performed on a pyramid or a cone having a height in the normal direction of the screen. It is good also as an element. In this case, it is possible to change the optical path of each partial light by moving the viewing angle adjusting member in any of the upper, lower, left and right directions with respect to the screen.
That is, the optical path of each partial light can be changed by arbitrarily changing the shape of the viewing angle adjusting element based on the state of each partial light emitted from the dividing member and the refractive index of the material constituting the viewing angle adjusting element. Can be determined.
In the above-described embodiment, the viewing angle adjustment member 64 includes a plurality of viewing angle adjustment elements 641. However, for example, by molding one member, the optical path of each partial light is reflected and changed internally. It may be.

In the embodiment, light substantially parallel to the principal ray of each partial light LS is incident on the left side surface 644 and the right side surface 643 at an angle of about 90 °, and is substantially refracted from a surface different from the back surface 642. However, it may be injected from the back surface 642. Note that the light emitted from the back surface 642 may be lost without being emitted to the front side of the screen 6.
In the above embodiment, the screen 6 is used for the rear projector 1, but it may be used for a display device using a transmissive screen.

  The present invention can be used for a screen, and in particular, can be suitably used for a screen used for a rear projector.

1 is a vertical sectional view of a rear projector according to an embodiment of the invention. FIG. 2 is a schematic diagram showing a schematic configuration of an optical system configured inside the projector unit in the embodiment. The horizontal direction sectional view which shows schematic structure of the screen in the said embodiment. The figure which shows the optical path of the chief ray at the time of moving the viewing angle adjustment member in the said embodiment to the right direction. The figure which shows the optical path of the chief ray at the time of moving the viewing angle adjustment member in the said embodiment to the left direction.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Rear projector, 3 ... Projector unit, 6 ... Screen, 62 ... Lenticular lens, 63 ... Black stripe, 64 ... Viewing angle adjustment member, 621 ... Cylindrical lens, 641 ... Viewing angle adjustment element, 642 ... Back surface, 643 ... Right side Surface, 644 ... Left side.

Claims (6)

A transmissive screen that projects image light projected from the back side to the front side,
A dividing member that divides the image light into a plurality of partial lights and emits the light;
A viewing angle adjusting member that reflects and changes the optical paths of the plurality of partial lights internally;
One of the viewing angle adjusting member and the dividing member is moved relative to the other, whereby the viewing angle adjusting member changes an optical path of the plurality of partial lights. screen. The screen of claim 1,
The screen is formed in a substantially rectangular shape,
The dividing member divides the image light in a direction of one side of the screen with a substantially uniform width,
The viewing angle adjusting member includes a plurality of viewing angle adjusting elements on which the plurality of partial lights respectively enter.
The viewing angle adjusting element is formed of a columnar body, and the viewing angle adjusting member is moved in the direction of the one side, whereby the optical path of the partial light is reflected and changed by the side surface of the viewing angle adjusting element. A screen characterized by doing. The screen according to claim 2.
The viewing angle adjusting element is
A rear surface facing the dividing member and receiving the partial light;
Two side surfaces facing in the direction of the one side,
In the two side surfaces, when the viewing angle adjusting member is moved in the direction of the one side, the light substantially parallel to the principal ray of the partial light is on one of the two side surfaces. A screen which is reflected and formed so as to be emitted from a surface different from the back surface. The screen according to claim 3,
The viewing angle adjusting element is
A screen having a substantially equilateral triangular prism when a columnar body is formed by extending the back surface and the two side surfaces. The screen according to any one of claims 1 to 4,
The principal rays of the plurality of partial lights are substantially parallel to each other.   An image projection apparatus that modulates light emitted from a light source according to image information to form image light and projects the image light in an enlarged manner, and a screen according to any one of claims 1 to 5. A rear projector characterized by that.

Images